This invention relates to the gas jet treatment of multifilament yarns and is more particularly concerned with the cleaning of deposits from apparatus employed for gas jet yarn treatment.
Continuous multifilament synthetic yarns are treated with gas jet apparatus in various yarn treatment processes such as texturing to increase the bulkiness of the yarn and interlacing to provide adequate handling characteristics to the yarn without the need for the introduction of twist to the yarn. Typically, apparatus for such gas jet treatment processes employs a pressurized gas such as air which is supplied to a jet device with a yarn treatment zone including at least one orifice which forms and directs a stream of air into the treatment zone. The yarn is conveyed through the treatment zone while being positioned with respect to the air stream to achieve the desired treatment.
In such apparatus, the flow pattern of the air in the treatment zone and the position of the yarns is usually critical to achieve the desired effect uniformly as the yarn is treated. However, deposits tend to build up on surfaces in the treatment zone which can affect the yarn treatment process. Typically, these deposits are gel-like and are composed of yarn finish solids, titanium dioxide, polymer skins and trimer which are blown off the yarns being treated. This is particularly a problem in interlace jets of the type disclosed in U.S. Pat. No. Re. No. 29,285. Such jets are provided by a number of spaced-apart, stacked ceramic plates resembling "tombstones" which have jets on one side surface and the opposite side of the plate serves as a striker surface for the jets of an adjacent plate. Yarns to be interlaced are passed in the slots between the plates and are guided by positioning pins past the jets. While a plastic comb-like device has been used to clean such apparatus, manual cleaning has not been found to be effective due to the size of the slots and the obstruction provided by the positioning pins, particularly since even small deposits left on surfaces in the treatment zone can result in non-uniform interlacing.